Apparatus for making emulsions of bituminous materials



M. G. ONEH.

Filed lJim@ 1o, 195e l x l n l II0H l I llolololnolalol l l lolvlhlolalnIUIIiO-Olololv u 0 u o a U 0 o 0 Q 0 6 APPARATUS FOR MAKING EMULSIONS OF BITUMINOUS MATERIALS Der; 2s, 1937.

ATTORNEY.

Patented Dec. 28, 1937 UNITED STATES PATENT OFFICE APPARATUS FOR MAKING EMULSIONS F BITURMNOUS MATERIALS Application June 10, 1936, Serial No. 84,489

1 Claim.

The present invention relates to the production of emulsions, and to improved apparatus for emulsiflcation. It finds particular application in the emulsication of a bitumen in an aqueous medium containing a soapy, or other, dispersing or emulsifying agent.

More particularly the invention is concerned with an improved process and apparatus for making emulsions of asphalt in water.

An object of the invention is to provide an improved process and apparatus for making emulsions of bituminous materials in water which emulsions are highly stable and in which the emulsiiied material is extremely nely divided and of uniform particle size.

A further object of the invention is to provide a process of emulsication which is carried out without the use of beaters or similar types of mixing units.

According to the process of the present invention, the material to be emulsied is gradually added, in small increments, to a circulating stream of dispersion medium (water, or aqueous fluid, including a suitable emulsifying agent) continuously led from and delivered to a main body of the dispersion medium, successive portions of the stream, under considerable pressure and at high velocity, being continuously injected into portions of the stream at materially lower pressure. thereby utilizing the cutting and disintegratng forces of the high velocity stream portions to reducethe particle size of the dispersed phase, the circulation and injection being continued until the particle size of the dispersed phase of the resulting emulsion has been reduced to the desired degree. As the dispersion medium I may, and preferably do, employ hot, relatively soft water containingdis'solved therein a suitable amount of an emulsifying agent (e. g., a soap). I may continue the circulation and injection of the liquid after the desired proportion of material to be emulsified has been introduced thereinto. Also, after the desired amount of material to be emulsied has gradually been introduced into the continuous phase and dispersed therein, in the manner above described, I may and preferably do continue the disintegration of the particles of the dispersed phase by continuing the circulation and injection while progressively increasing the velocity of the injected stream portions, or their pressure, or both. This latter I may eect by progressively decreasing the size of the openings through which the 'stream portions are forced, under pressure, into the stream portions of lower pressure.

The process hereinafter will be described in greater particularity in conjunction with a preferred form of apparatus for carrying it into effect, which apparatus also forms a part of the invention.

This apparatus is illustrated in the accompanying drawing, wherein:

Fig. 1 is a plan view of the assembled equipment embodying the invention;

Fig. 2 is a side elevation thereof;

Fig. 3 is a vertical sectional view through the emulsifying unit, taken on the line 3 2. of Fig. 1;

Figure 4 is a sectional view on the line 4-4 of Figure 3;

Figure 5 is a sectional view on the line 5-5 of Figure 3; and

Figure 6 is a sectional view on the line 6-6 of Figure 4.

Referring now more particularly to the drawing, A is a tank containing asphalt to be emulsifled. Suitable heating means, such as steam coils, not shown, are provided to maintain the asphalt at the proper temperature, it being desirable to add the asphalt hot. A water container W is provided, the same being calibrated in gallons and, as will become apparent hereinafter, determines the degree of concentration by the rising level of the emulsion, hence no measuring meters are necessary. The container isv provided also with suitable means, not shownr'for maintaining the proper temperature of liquid in the container. v

The tank A is connected by a conduit-I Ib to a pressure pump 9, there being a control valve IIa to govern the delivery of material from the tank A. A conduit IIc leads from container W and connects with the conduit `I Ib on the intake side ofthe pump 9, a control valve IIa being located in the conduit IIc. A suitable' motor M is provided for driving the pump 9. f

The delivery side of the pump 9 is connected by a pipe I4 to an emulsifying unit 8 which consists of `a metal shell, preferably cylindrical in shape, and divided by a horizontal partition wall I9 into a large upper compartmenty I1 and a smaller lower compartment I8'. The partition wall I8 is provided with a number of threaded openings into which the lower ends of perforated pipes are threaded.

These pipes are divided into sets, and designated as I2, I5 and I6 having different vsized perforations, those in pipes I5 being smaller than in pipes I2, and those in pipes I6 being smaller than in pipes I5.

The 'perforated pipes are disposed in the compartment or chamber I1 and are partially covered by rotary sleeve valves 20 which nt over the upper ends of the pipes, the sleeve valves having closed upper ends which serve as caps for closing the upper ends of the tubes. It will be noted that the Valve sleeves 20 are imperforate exceptl for an elongated passage or slot 20a in the side thereof, and also that the perforations in the tubes I2, I5 and I6 extend only part way around the tubes so that they may be partially or wholly covered by the imperforate portion of the sleeve valves 20 to regulate the ilow from compartment I'I to compartment I8.

'I'he sleeve valves 20 are provided with stems extending through the top of the unit 8 and handles Iza, I5a and I6a are mounted on the stems for operating the valves.

By reference to Figs. 1 and 3, it will be noted that the pipe I4 delivers fluid from the pump 9 to the chamber I I and that the pipe Ila leads from the chamber I8 back to the tank W.

In carrying outthe process of the present in- Vention utilizing the apparatus described, assuming that it is desired to produce 2,000 gallons of an emulsion having an asphaltic content of 50 per cent, with all valves closed, 1,000 gallons of hot soft water is placed in the calibrated tank W. .An emulsifying agent such as a soap solution is added to the water in an effective amount, and the mixture is maintained at a temperature of not less than 180 F. 'I'he pump 9 is then started into operation and the valve I la is opened to allow the mixture of water and emulsifler to ow into the chamber I1, through the perforations in the pipes I2 which will be opened into the discharge chamber I8 and back to the tank W.

The valve II is then opened gradually to admit a relatively small stream of the hot asphalt from the tank A into the circulating stream of water and emulsifying agent, a proportion of one part of asphalt to about three parts of water being preferable. The resulting mixture of materials is then forced by the pump 9 into the chamber I'I under high presure and through the perforations in the pipes I2 where it is impacted under high pressure into the moving stream or body of the constantly increasing dispersed phase at a lower pressure in the pipes I2 and discharge'chamber I8, from which latter the mixture is nally returned to the tank W. As the materials are con'- stantly recirculated as the addition of the asphalt proceeds, the concentration of the dispersed phase will constantly increase until the desired concentration is reached.

The desired concentration is determined by the rising level of the emulsion in the container W and having been reached and the supply of asphalt stopped by closing valve II, the valves on pipes I2 will be closed and one of the succeeding series I5, l5 or I6, I6 selected, each of which have smaller perforations than the preceding series.

The selection of the series of perforated tubes to be used will be governed by the hardness of the bitumen used and of the vdegree of heat contained in it. 'I'he object being to carry the process to that pofint where the cutting and disintegrating action of the numerous high-pressure sprays will have reduced, by their discharge under pressure into an area of lower pressure, the particle size of the dispersed phase to the degree required.

It will be seen that the pressure in the emulsiiler 8 will be controlled within the limits of the power of the pump by making use of a greater or less number of the perforations in the tubes during the operation.

The pressure on chamber I8 and pipe Ila is maintained relatively low by reason of their having a greater carrying capacity than the ability of the pump to produce. This in turn keeps the same low pressure inside of the perforated tubes through which the materials are forced.

From the description of the process, it will be seen that I carry out the following steps which I claim to be new and necessary for the results to be obtained.

First: The materials are combined at a low concentration and gradually increased to the desired concentration over a considerable period of time, during which time the materials are continually in motion and being disintegrated by a plurality of high pressure streams impinging on each other and into the moving stream of emulsion as the same is being formed.

Second: This process accomplishes the accurate proportioning of the ingredients 4through the use of calibrated containers.

Third: I avoid the use of beaters or stirring blades, thereby preventing an increase of particle size by compaction of the heavier materials with the blades or with each other. The release of the combined liquid materials through successively smaller nozzles and from a relatively high pressure to a lower pressure disintegrates the particles into smaller units.

While a preferred form of the invention has been shown and described, it is to be understood that various modications in the details of the Y compartment and opening at .one end into said' low pressure compartment, meansfor closing the other end of said pipes and for regulating the iiow of liquid through said perforations in the pipes, said means comprising sleeve valves mounted on said pipes, said sleeve valves being imperforate and having an elongated slot in one side thereof, said perforations in said pipes extending only part way around the pipes, a connection from said pump to said high pressure compartment and a connection from said low pressure compartment back to said liquid tank.

` M. GRIFFIN ONEIL. 

